1. Field of the Invention
The present invention relates to a cosmetic or dermatological powder containing at least one electrolyte, to a process for its manufacture and to a composition containing it. More particularly, the invention relates to the use of the powder or of the composition for the care and/or treatment of the skin, mucous membranes and/or the scalp, as well as for the treatment of skin disorders.
2. Description of the Background
Compositions containing electrolytes (inorganic and organic salts), which are useful for their beneficial effects on the skin, are known in cosmetics and dermatology. Certain electrolytes make it possible, in particular, to treat problems of sensitive skin and the pathological or physiological disorders associated with the release of substance P and/or TNF-alpha (Tumor Necrosis Factor-alpha) and in particular to treat sensitive skin, skin disorders and skin diseases. Such compositions are described, for example, in EP 0 737 471, EP 0 770 392 and EP 0 775 492.
Moreover, it is known that the incorporation of electrolytes into cosmetic or dermatological compositions containing water poses problems, because of the incompatibility of electrolytes with certain constituents usually employed in such compositions. Thus, for example, electrolytes are incopatible with the neutralized caboxyvinyl polymers usually used as gelling agents, since they "break" the emulsion and liquify it. As a result, compositions containing caboxyvinyl polymers and electrolytes lack consistency, which is counter to the result desired when a gelling agent is used.
It has now been found, unexpectedly, that it is possible to prepare a composition which is free of the drawbacks of the compositions of the prior art by incorporating electrolytes into an anhydrous powder containing a modified starch and which can contain at least one fatty substance.
Admittedly, JP-A-7/206,663 describes a bath powder containing inorganic salts, sugars and fatty substances. However, this powder has the drawback of being sensitive to moisture and bacteriological contamination. A need therefore continues to exist for salt-containing cosmetic compositions of improved pathological and physiological properties which are less sensitive to water and bacteriological contamination.